Counting circuit for coin counting device

ABSTRACT

An electrical circuit arrangement for use in a coin counting device is provided. The arrangement is provided with an abnormality detection circuit for generating an alarm signal when any of the optical sensing member of the coin counting device is hindered from operating normally due to adhesion of dust or other causes. The abnormality detection circuit includes a NAND gate, a NOR gate, an OR gate, a counter and an SR-type flip-flop. The first and second detection signal generated from the optical sensing members are supplied to the NAND gate and the NOR gate. The OR gate is supplied with the output from the NOR gate and a reset signal from a reset operator section. The counter is supplied with the output from the NAND gate and the output from the OR gate. In normal operation, the counter counts the level &#34;1&#34; and &#34;0&#34; of the binary logical level alternately, thereby to leave a counting section to continue the counting operation. If any abnormality occurs at any of the combined optical sensing members, the number counted by said counter takes the value 2, whereupon a second output signal indicating the occurrence of abnormality is generated by the counter and fed to the flip-flop which generates an alarm signal.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a counting circuit arrangement for acoin counting device, and particularly to a circuit arrangement providedwith an alarm generating section for generating an alarm signal whendust or other foreign matter adheres to the optical counting elements ofthe system for counting coins.

2. Prior Art

Optical counting systems for counting passing coins have been known inthe art. An illustrative example of the known optical counting systemsis shown in FIG. 1. Referring to FIG. 1 showing main parts of theillustrative example, the structure and operation of the known systemwill be outline.

In FIG. 1, coins are charged on a rotary disk 1 rotating in thedirection shown by the arrow A, and then introduced to a coin passage 2successively one by one. The coins are passed through the coin passage 2under the action of a guide belt 3 to a coin accumulator tube 4 in whichthey are accumulated. Along the coin passage 2, there are provided astopper pin 5 to open or close the coin passage 2 and two photosensors 6and 7 for detecting the coins passing through the coin passage 2. Alight emitting element (not shown) is disposed above the photosensors 6and 7 in opposed relationship to the photosensors, and the passing coinsinterrupt the light paths from the light emitting element to thephotosensors 6 and 7.

The photosensors 6 and 7 detect the traveling direction of the passingcoins and simultaneously count the number of the coins passingtherethrough. The counted coins are introduced into the coin accumulatortube 4. When the number of coins accumulated in the accumulator tubereaches the pre-set number, the stopper pin 5 is rotated by 90° byrotary solenoid (not shown) in the direction shown by the arrow B tostop the feeding of coins to the accumulator tube 4.

However, in the prior art device, if dust or other foreign matter shouldadhere to either one of the photosensors 6 or 7, the moving direction ofthe coins cannot be detected and only the passage of coins can bedetected, resulting in miscounting. There is another problem that asignal causing the miscounting in the counting circuit might begenerated when dust or other foreign matter adheres to either one of theoptical elements or due to reduction in illuminating power of the lightemitting element to lessen the quantiy of light incident onto thephotosensors 6 and 7.

OBJECT AND SUMMARY OF THE INVENTION

The primary object of the present invention is to overcome theaforementioned problems or disadvantages of the prior art device.

A more specific object of the present invention is to provide a countingcircuit arrangement having an alarm signal generating section forgenerating an alarm signal when dust or other foreign matter adheresonto any of the optical elements for sensing the passing coins.

Another specific object of the present invention is to provide acounting circuit arrangement having an alarm signal generating sectionfor generating an alarm signal when the illuminating power of the lightemitting element is reduced with the lapse of time.

The aforementioned objects can be attained, according to the presentinvention, by the provision of a counting circuit arrangement for a coincounting device comprising a light generating section having a lightemitting element, first and second light receiving sections respectivelyhaving first and second photosensors arranged close to each other forreceiving light from said light emitting element when they are notcovered by any passing coin and for generating detection signals whenthey are covered by any of the passing coins, an addition-subtractiondiscriminating section for receiving output signals from said first andsecond light receiving blocks to put out a count-up or count-downsignal, a counter section for receiving the signal from saidaddition-subtraction discriminating section to count the number of coinspassing through said first and second photosensors, and an abnormalitydetection section connected in parallel with said addition-subtractiondiscriminating section to receive output signals from said first andsecond light receiving sections and to put out an alarm signal inresponse to a difference in the number of pulses between the outputsignals from said first light receiving section and the output signalsfrom said second light receiving section.

DESCRIPTION OF THE DRAWINGS

The above and other objects and advantages of the present invention willbecome apparent from the following detailed description of the preferredembodiment with reference to the accompanying drawings, in which:

FIG. 1 is a plan view showing diagrammatically a portion of a coincounting device of the prior art which may be combined with the countingcircuit arrangement of the invention;

FIG. 2 is a block diagram showing one embodiment of the counting circuitarrangement according to the invention;

FIG. 3 shows a electric circuit constituting the abnormality detectionsection included in the circuit arrangement shown in FIG. 2; and

FIGS. 4(a) and 4(b) are diagrams showing the wave forms and timing ofcontrol operations in the circuit arrangement according to theinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention will now be described in detail by referring to apresently preferred embodiment thereof shown in the appended drawings.

Firstly referring to FIG. 2 showing an electric circuit arrangementembodying the present invention, a light generating section including aknown light emitting element is denoted by numeral 10. The lightemitting element of the light generating section 10 is opposed tophotosensors 6 and 7 positioned closely adjacent to each other. Thelight paths from the light emitting element of the photosensors 6 and 7traverse the coin passage 2, so that they are intermittently covered bythe passing coins. The photosensors 6 and 7 are, respectively, includedin first and second light receiving sections 11 and 12.

The first light receiving section 11 includes the photosensor 6, such asa photodiode, and a comparator for converting the electric signal fromthe photosensor 6 into a binary code signal "1" or "0" of the binarylogical level. When the light path to the photosensor 6 is shielded by apassing coin, a first detection signal SA (SA="1") is fed from thislight receiving section 11 to an addition-subtraction discriminatingsection 13 and an abnormality detection section 14.

Similarly, the second light receiving section 12 includes thephotosensor 7 and a comparator for converting the electric signal fromthe photosensor 7 into a binary code signal "1" or "0" of the binarylogical level. When the light path to the photosensor 7 is shielded by apassing coin, a second detection signal SB (SB="1") is fed from thislight receiving section 12 to the addition-subtraction discriminatingsection 13 and an abnormality detection section 14.

The addition-subtraction discriminating section 13 receives the firstand second detection signals SA and SB to discriminate the sequentialorder of these signals, namely determining the moving direction of thecoin, to put out an addition signal UP or a subtraction signal DN to acounting circuit section 15.

The counting circuit section 15 includes an updown counter and acomparator for comparing the counted number to a pre-set numberinstructed by digital switches or the like. When the counted numbercounted by the up-down counter reaches the pre-set number, a coincidentsignal CL is generated and delivered to a driving section 16 of acount-stopping device.

Upon actuation of the driving section 16 of the count-stopping device, arotary solenoid 17 is driven and a coin feed motor 18 is stopped. As aresult, the stopper pin 5 is rotated in the direction of arrow B, asshown in FIG. 1, by the action of the rotary solenoid 17 to block thecoin passage 2. On the other hand, the coin feed motor 18 is stopped tostop rotation of the rotary disk 1 and to stop conveying movement of theguide belt 3.

The abnormality detection section 14 includes, as shown schematically inFIG. 3, a NAND gate 19, a NOR gate 20, an OR gate 21, a counter 22 andan SR type flip-flop (hereinafter referred to as SRFF) 23. The first andsecond detection signals SA and SB are, respectively, supplied to theinput terminals of the NAND gate 19 and the NOR gate 20. On the otherhand, the input terminals of the OR gate 21 are supplied with the outputsignal S1 from the NOR gate 20 and a reset signal RS from a resetoperation section 24. The counter 22 has a clock terminal C to which anoutput signal S2 fron the NAND gate 19 is supplied, and a reset terminalS to which an output signal from the OR gate 21 is supplied. The SRFF 23has a set terminal S to which a second output signal S3 from the counter22 is supplied, and a reset terminal R to which the reset signal RS issupplied. The second output signal S3 of the counter 22 is fed from asecond output terminal of the counter 22 such that the second outputsignal S3 takes the level "1" when the counter 22 counts the number 2.When this second output signal S3 is generated from the counter 22, theSRFF is set to deliver an alarm signal AL to the driving section 16 ofthe count-stopping device and to an alarm display section 25 having alight emitting element or other suitable means. As a result, the coinpassage 2 is blocked and the light emitting element is put on toindicate the occurrence of an abnormal state.

The operation of the alarm circuit arrangement of the abnormalitydetection section 14 will now be described with reference to the waveform chart of FIG. 4.

The waves generated when a coin passes under normal condition throughthe coin passage 2 to the coin accumulator tube 4, are shown in FIG.4(a). On the other hand, FIG. 4(b) shows the waves generated when anyabnormality is sensed, for instance, when dust adheres to thephotosensor 7 in the course of the counting operation to hinder thephotosensor's sensing of the passing coin.

In the normal operation, the first and second detection signals SA andSB are generated every time a coin is passed through the photosensors 6and 7. The signals generated as a result of the passage of a successionof coins are fed to the addition-subtration discriminating section 13from which addition signals UP in a number same as that of the number ofpassing coins are fed to the counting circuit section 15.

In the abnormality detection section 14, the output signal S2 of theNAND gate 19 rises up at the time t₁ when a certain coin shields thelights incident upon the photosensors 6 and 7 and then permits thephotosensors 6 to be exposed to the incident light again. In responsethereto, the counter 22 counts 1. At the time t₂ when the photosensor 7is again exposed to the incident light, the output signal S1 of the NORgate 20 takes the level "1" so that the counter 22 is reset. As will beseen from the foregoing description, the abnormality detection sectiondoes not put out the alarm signal AL under normal operation condition.

Assuming now that the photosensor 7 is prevented from sensing light dueto adhesion of dust at a time t₃. After that time, the second detectionsignal SB continuously takes the level "1" irrespective of the passingof the next coin through the photosensor 7. Also, theaddition-subtraction discriminating section 13 does not generate theaddition signal UP at that time. When the second detection signal SBtakes the level "1", the output signal S1 from the NOR gate is broughtto "0" so that the counter 22 is not reset. At a time t₄ when the nextcoin passes through the photosensor 6, the counted number on the counter22 reaches 2, whereby the SRFF 23 is set. Whereupon, the SRFF 23generates the alarm signal AL which is fed to the alarm display section25 and also to the driving section 16 of the count-stopping device.

As a result, counting operation is stopped and the alarm light is lit.

It will be clearly understood by those skilled in that are from theteaching disclosed herein that the coin counting device is preventedfrom making a mis-counting operation by the provision of the abnormalitydetection section incorporated in the electrical counting circuitarrangement. By the incorporation of a simple but yet reliableabnormality detection block as specifically disclosed herein, an alarmsignal is generated when dust or other foreign matter adheres to any ofthe optical sensing elements or any of the sensing elements isdeteriorated by some cause. It should be also apparent to those skilledin the art that the construction and arrangement of the embodiment canbe changed or modified without departing from the spirit and scope ofthe present invention. For example, although an abnormality is sensed inresponse to the first and second detection signal Sa and SB in theillustrated embodiment, two counters each for integrating or adding thefirst and second signals individually may be provided and an abnormaloperation be detected by comparing the added numbers of these twocounters. Many other changes or modifications may be made by thoseskilled in the art in the light of the foregoing teachings. Accordingly,the foregoing description is not construed as a limiting sense butshould be construed as illustrative only. The scope of the presentinvention is limited only by the appended claims.

What is claimed is:
 1. A counting circuit arrangement for a coincounting device, comprising a light generating section having a lightemitting element, first and second light receiving sections respectivelyhaving first and second photosensors arranged adjacent to each other forreceiving light from said light emitting element when they are notcovered by any passing coins and for generating detection signals whenthey are covered by any of the passing coins, each said light receivingsections having a normal unobstructed sensitivity, anaddition-subtraction discriminating section for receiving output signalsfrom said first and second light receiving sections to generate acount-up or count-down signal in dependence on the order of reception ofthe output signals from the first and second light receiving sections, acounter section for receiving the signal from saidadditional-subtraction discriminating section to count the number ofcoins passing through said first and second photosensors, and anabnormality detection section for detecting the difference between thesensitivities of said first and second light receiving sections, saiddetection section being connected in parallel with saidaddition-subtraction discriminating section to receive output signalsfrom said first and second light receiving sections and to produce analarm signal in response to the difference in sensitivities determinedby the difference in number of pulses between the output signals fromsaid first light receiving section and the output signals from saidsecond light receiving section.
 2. A counting circuit arrangement for acoin counting device, comprising a light generating section having alight emitting element, first and second light receiving sectionsrespectively having first and second photosensors arranged closelyadjacent to each other for receiving light from said light emittingelement when they are not covered by any passing coins and forgenerating detection signals when they are covered by any of the passingcoins, an addition-subtraction discriminating section for receivingoutput signals from said first and second light receiving sections togenerate a count-up signal when the first light is received before thereceipt of the second light and a count-down signal when the first lightis received after the receipt of the second light, a counter section forreceiving the signal from said addition-subtraction discriminatingsection to count the number of coins passing through said first andsecond photosensors, and an abnormality detection section connected inparallel with said addition-subtraction discriminating section toreceive the output signals from said first and second light receivingsections and to produce an alarm signal in response to a predetermineddifference in number of pulses between the output signals from saidfirst light receiving section and the output signals from said secondlight receiving section, said abnormality detection section including aNAND gate for receiving said output signals from said first and secondlight receiving sections, a NOR gate for receiving said output signalsfrom said first and second light receiving sections, an OR gate forreceiving the output from said NOR gate and a reset signal from a resetoperator section, a counter for receiving the output signal from saidNAND gate and the output signal from said OR gate, and a set-resetflip-flop for receiving the output signal from said counter and resetsignal to generate an alarm signal when a second output signalindicating occurrence of any abnormal condition is fed thereto by saidcounter.